虚拟语态的概述

1．虚拟语气在条件句中的用法

（1）若表示与现在事实相反的假设，则条件从句中用过去式，主句中用过去将来式（would，should，could，might + 动词原形）；若表示某事将来实现的可能性不大，则条件从句中用should + 动词原形也可用“were to+动词原形”或用过去式动词。如：

J I would certainly go if I had time．（现在）

J If it should rain，we wouldn't go out.（将来）

J If I knew German，I would read the paper to you．（现在）

J If he were here，we could ask him．（现在）

（2）若表示与过去事实相反的假设，从句中用过去完成式，主句中用过去将来完成式（should，would，could，might + have + 过去分词）。如：

J If I had set off a little earlier， I would have caught the train．

J She would / might have come if she hadn't been so busy．

J If I hadn't taken your advice，I would have made a bad mistake．

J If only you hadn't told him the news．

（3）含有虚拟语气的条件状语从句中，如有had，should，were 这三个词的话，在正式或书面语言中可将if省略，再将句子的主语和谓语动词实行全部倒装或部分倒装。如：

J Had they time（=If they had time），they would certainly come and help us．

J Should it be fine（=I